don't assume we can use gcc 2.96+ options

ares/configure.ac

@@ -31,7 +31,9 @@ AC_HELP_STRING([--disable-debug],[Disable debug options]),
     CPPFLAGS="$CPPFLAGS -DCURLDEBUG"
     CFLAGS="$CFLAGS -g" 
     if test "$GCC" = "yes"; then
-       CFLAGS="$CFLAGS -W -Wall -Wwrite-strings -pedantic -Wno-long-long -Wundef -Wpointer-arith -Wnested-externs -Wcast-align -Winline -Wstrict-prototypes -Wmissing-declarations -Wmissing-prototypes -Wshadow -Wfloat-equal -Wsign-compare -Wunreachable-code"
+       dnl these work for gcc 2.95
+       CFLAGS="$CFLAGS -W -Wall -Wwrite-strings -pedantic -Wno-long-long -Wundef -Wpointer-arith -Wnested-externs -Wcast-align -Winline -Wstrict-prototypes -Wmissing-declarations -Wmissing-prototypes -Wshadow -Wsign-compare"
+       dnl 2.96 or higher: -Wfloat-equal -Wunreachable-code
     fi
     dnl strip off optimizer flags
     NEWFLAGS=""